Gina Rinehart has consolidated her position as Australia's wealthiest person with the prominent magazine Forbes saying the mining magnate's net wealth jumped to $US15 billion ($19.4 billion) over the past 12 months.

In what was a record year for the number of uber-wealthy around the world, Forbes said Ms Rinehart's position on their annual index skyrocketed from 127 in 2016 (with a fortune of $US8.8 billion) to the 69th spot in 2017, making her the only Australian in the top 100. According to the index, her wealth has climbed by $US6.2 billion ($8 billion) over the last year.

It was a different story for the newly-minted US President Donald Trump, whose wealth shrunk to $US3.5 billion on the back of a softening New York property market. It sees Mr Trump tumble more than 200 spots to No.544 on the list.

The magazine said Ms Rinehart was the female billionaire who had the "best year" but noted that with Ms Rinehart's wealth built on iron one, "her fortune can either jump or plummet depending on the price of the commodity."

"Unlike all the other women ahead of her, Rinehart also has bragging rights for actively building her fortune. Rinehart took her late father's bankrupted estate and rebuilt it into something much larger," says Forbes.

But the West Australian is a controversial figure in Australia because of her links to prominent right-wing politicians and support for lower wages for Australian workers citing international competitiveness. Last year Ms Rinehart praised Mr Trump's election and called for a replica of his policies in Australia, in a speech delivered on her behalf by the former Liberal MP Sophie Mirabella.

Ms Rinehart is a personal friend of the deputy prime minister and Nationals leader Barnaby Joyce and attended his maiden speech when he switched from the Senate to the lower house in 2013.

In 2011, Ms Rinehart flew Mr Joyce and the deputy Liberal Leader Julie Bishop and another coalition MP to India to attend a wedding in the wealthy Reddy family.

Property developer Harry Triguboff was Australia's second highest ranked billionaire at number 153 with a net worth of $11 billion.

The founder of the Australian software firm Atlassian debuted as the youngest on the Billionaires List. Mike Cannon-Brooks is said to have a net worth of $2.7 billion.

Forbes says it calculates the wealth of the listed billionaires by using stock prices and exchange rates to calculate their net worth as of February 17, 2017.

Microsoft founder and philanthropist Bill Gates topped the list for the fourth time in a row with a net worth of $112 billion. Facebook founder Mark Zuckerberg moved up into fifth position.

The magazine said it was a "record year" for the world's richest, with the number of billionaires increasing by 13 per cent to 2,043 and their combined value jumping by 18 per cent to $9.9 trillion.